ByTakehiko Kambayashi, CorrespondentSeptember 5, 2014

Activist Yoon Mee-hyang stands next to a butterfly flag at the War and Women’s Human Rights Museum in Seoul, South Korea. Butterfly flags are used at demonstrations calling for recognition of the rights of former sex slaves.

Yoon, representative of the Korean Council for the Women Drafted for Military Sexual Slavery by Japan, says that as Japan has shown an increasingly conservative bent, her group has gotten more harassing e-mails and phone calls like that.

Critics say Mr. Abe has played a leading role in glossing over Japan’s wartime history, which has aggravated relations with neighboring countries. When Yoon and elderly survivors of the brothels visited the office building of Japanese lawmakers in June, a group of Japanese protesters showered them with a barrage of abuse, even calling the victims “prostitutes.”

“That was frustrating,” Yoon concedes.

Since 1990, the Korean council has been working on exposing the sexual slavery issue to restore the dignity and rights of victims.

Historians say the number of victims ranged from tens of thousands to 200,000. As Japan was about to be defeated in 1945, the women were abandoned or killed by Japanese soldiers or in Allied bombings.

After the war, because of the stigma of prostitution, the victims were reluctant to talk about their suffering.

During his meeting with South Korean President Park Geun-hye in Seoul in April, President Obama called Japan’s sexual slavery during World War II a “terrible and egregious violation of human rights.”

The issue is so serious and tragic that when Yoon was first working on it, she says, she occasionally fell into depression.

“I was going through an agonizing period and could not even laugh,” she recalls.

She was gradually able to overcome her difficulties as she got better acquainted with survivors of the wartime brothels. “I have learned hope from them and have been empowered,” she says.

Of the 237 South Korean victims that have registered with the South Korean government, only 54 are still alive.

When Yoon first became involved, about 20 years ago, “survivors were seen as disgraceful. They were viewed with prejudiced eyes,” she says. Many South Koreans did not show interest in the issue or in the council’s work, she adds.

These days, however, more young people have realized it is a shame that they did not know about the victims of sexual slavery and their hardships, Yoon says. “The change clearly shows social advancement in this country.”

Such progress helped lead to a landmark ruling by the South Korean Constitutional Court in August 2011, she says. The court ruled that it was unconstitutional that the government had made no efforts to persuade Japan to compensate victims of sexual slavery, thereby infringing on the victims’ basic human rights.

The decision bolstered the council’s work. Today an increasing number of people, including surviving victims, take part in demonstrations every Wednesday in front of the Japanese Embassy in Seoul, demanding reparations and apologies.

During South Korea’s election campaigns in early June, the number of participants grew to about 1,000, according to the council, which organizes the demonstrations.

The group asks participants not to hoist a South Korean flag, Yoon says. Instead it uses an image of a softly colored butterfly, an effort to attract children and young people. On the occasion of the 1,000th demonstration in December 2011, the council also put up what it called the “Peace Statue,” a bronze statue of a young girl that directly faces the Japanese Embassy across the street.

Japanese activists who support the survivors and the work of the council have marveled at Yoon’s dynamism.

Sumiko Nishimura, who heads the Kansai Network, based in Osaka, Japan, which seeks to have Japan apologize for its actions, says Yoon has been a strong force for the movement.

The opening of a long-awaited museum on the history of Japan’s wartime sexual slavery has also helped more young people become interested in the issue, Yoon says. The War and Women’s Human Rights Museum in Seoul took more than eight years to build, opening in 2012.

Survivors themselves donated to the project, as they never wanted to see the world create victims like them again. The South Korean government also provided some funds at the last minute after it was criticized for not having done so.

While labor unions contributed money, South Korean corporations, concerned about losing Japanese clients, provided no support, Yoon says. “That will certainly go down in the history,” she says with a smile.

In May 2013, Yoon and two Korean survivors were invited by Ms. Nishimura to a symposium in Osaka. The event attracted an overflow crowd. “Ms. Yoon knows Japanese politics and society very well,” Nishimura adds. “She has also been expanding the group’s network overseas and addressed issues of current wartime sexual violence in other countries.”

Resolving the issue of sexual servitude during World War II could be important to victims of sexual violence in today’s armed conflicts, Yoon says. Setting a precedent by condemning these war crimes shows that “we can change the world,” she says.

“I admire her sincerely...,” says Yang Ching Ja, a leader of Japan Action Resolution of the Comfort Women Issue in Tokyo, a group that supports the work of the Korean council. “She also has sound judgment and comes up with wonderful ideas. She works harder than anyone. She sometimes sounds tired at night; however, on the next morning, she starts to talk about hope.”

Yoon also has opportunities to talk to students at high schools and universities about Japan’s wartime sexual slavery.

“I always tell them that we should not place a demand only on Japan in order to resolve this issue,” she says. “South Korea also needs to consider its own problems very seriously.”

Her talks include discussions about human trafficking in her own country, and the practice of South Korean men paying for sex during overseas business trips. “I look students in the eyes and say to them, ‘Please educate your fathers,’ ” Yoon says.

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